1. Field of the Invention
The present invention relates to an automatic splitter shifting in a manually shifted compound transmission having a lever-shifted main section connected in series with an auxiliary splitter or splitter-and-range section. In particular, the present invention relates to a prediction of a single, unique destination gear that is combined with splitter and range actuation logic rules, which enables engine and transmission control throughout the entire shift event. Thus, the operator may perform shifts without manipulating the clutch or throttle pedal, including a splitter button initiated compound shift.
2. Description of the Related Art
Controller-assisted, manually shifted transmission systems are known in the prior art, as may be seen by reference to U.S. Pat. Nos. 5,582,558; 5,755,639; 5,766,111; 5,791,189; 5,974,906; 5,989,155 and 6,015,366, the disclosures of which are incorporated herein by reference.
Compound transmissions having a range and/or combined range-and splitter-type auxiliary transmission section are well known in the prior art, as may be seen by reference to U.S. Pat. Nos. 4,754,665 and 5,390,561, the disclosures of which are incorporated herein by reference.
Transmissions having manually shifted main sections and automatically shifted splitter sections are known in the prior art, as may be seen by reference to U.S. Pat. Nos. 5,435,212; 5,938,711; 6,007,455 and 6,044,721, the disclosures of which are incorporated herein by reference.
Compound transmissions having automatically implemented range shifting are well known in the prior art, as may be seen by reference to U.S. Pat. Nos. 5,911,787 and 5,974,906, the disclosures of which are incorporated herein by reference.
To allow additional automation of the shift event, logic is required to determine destination gear and manage the actuation of the transmissions' auxiliary shift actuators (the range and the splitter), as well as the engine when the front box is in neutral (front box gear is equal to zero). Once shift event logic is in place, a transmission shift can be initiated based solely on the change in state of the splitter button and completed without the operator having to manipulate the clutch or throttle pedal. Combining the shift event logic with the already existing progressive shift logic adds additional robustness to the decision to initiate an upshift. In addition, combining shift event logic with throttle pedal input that communicates an idle position contributes additional robustness to the decision to initiate a downshift.